Apparatus for producing an insulated stream of hot fluid



April 19, 1960 c. D. SPANGLER APPARATUS FOR PRODUCING AN INSULATEDSTREAM OF HOT FLUID Filed Dec. 27, 1955 INVENTOR. J 'pan F161 H'Z' l' Fi gt 2 C arle fonD.

United States Patent APPARATUS FOR PRODUCING AN INSULATED STREAM OF HOTFLUID This invention pertains to the art of producing heat, and relatesparticularly to an apparatus by which to obtain from a given quantity offuel substantially increased amounts of heat available for useful work.

This application is a continuation-in-part of my now abandoned earlierapplication, Serial No. 176,875, filed July 31, 1950, and entitledProcess of Burning Fuel.

In conventional heat producing systems, particularly those which utilizecombustible materials as the source of heat, it has been the generalpractice heretofore to :achieve a high degree of turbulence in the heatproducing chamber in order to effect complete mixing of the fuel andassure complete combustion. Although the latter effect generally isachieved, the creation of such turbulent mixing necessarily results inthe transfer of heat from the particles heated by combustion to all ofthe remaining particles of the air or other fluid introduced into thecombustion chamber. Such transfer also results in substantial heating ofthe combustion chamber walls. Accordingly, it is evident that suchdilution of heat throughout the entire mass of the combustion chamberresults in a substantially lower output of heat from the chamber, i.e.the net heat ultimately available for useful work.

It is the principal object of the present invention to provide anapparatus by which the foregoing undesirable turbulence and consequentdilution of heat is eliminated and maximum available heat is obtained.

Still another important object of this invention is to provide anapparatus for producing a stream of hot fluid in such manner as toaccommodate the transport of such heat without significant loss from thearea of production to a point for conversion into useful work.

Another important object of this invention is the provision of anapparatus for producing a directed stream :of hot fluid confined withinan insulating envelop of cool fluid.

'A further important object of the present invention is to provide heatproducing apparatus in which the heat chamber requires no thermalinsulation and yet is not subjected to the intense heat generatedtherein.

A still further important object of the present invention is to provideheat producing apparatus which is of simplified construction foreconomical manufacture, which is of minimum size for the production of agiven quantity of heat, and which is capable of eflicient operation witha minimum of maintenance and is operable with maximum facility.

The foregoing and other objects and advantages will appear from thefollowing detailed description, taken in connection with theaccompanying drawings, in which:

Figure l is a view in side elevation, partly in section, of heatproducing apparatus embodying the features of the present invention;

Figure 2 is a fragmentary sectional view taken along the line 2-2 inFigure 1, showing a construction of the inlet port of the apparatus ofthe present invention;

Figure 3 is a sectional view taken along the line 3-3 in, Figure 1 andshowing by arrows the concentric flow of separated fluids at the outputof the apparatus; and

Figure 4 is a schematic representation of the apparatus of Figure 1including the outlet delivery pipe and the inlet sources of fuel andair.

As stated hereinbefore, conventional heat producing systems of the fuelcombustion type purposely are constructed and operated in such manner asto achieve maximum turbulence of the combustion supporting materialswithin the heat chamber in order to assure complete combustion. Becauseof such turbulence, the rapidly moving particles of gas which have beenheated move about in random manner, colliding with slower movingparticles which have not been heated. As a result of these collisions, aportion of the heat potential of the heated particles is transferred tothe cooler particles, thereby diluting the heat throughout the system.Furthermore, the randomly moving particles within the heat chambercollide with the chamber walls which, in turn, receive a portion of theheat potential of the particles, further diluting the heat and reducingthe heat output ultimately available for useful work.

Referring now to the drawings, the heat-producing apparatus of thepresent invention is shown to include a cylindrical heat chamber havingside walls 10 and a bottom closure 12. The open end of the chamber isremovably closed by a cap member which, in the embodiment illustrated,includes an outwardly constricted exhaust hood 14 and a peripheralmanifold 16 forming an annular chamber 18 therein which communicatesthrough feed pipe 20 and control valve 21 with a source (not shown) ofair or other oxidizing gas. Adjacent the lower inner side of themanifold the latter is offset upwardly to form a groove 22 adapted to bereceived over the open end of the heat chamber. The base of the grooveforms a shoulder 24 adapted to rest upon the upper end of the heatchamber. If desired, a ring-shaped seal 26 may be interposed between theshoulder and the adjacent edge of the heat chamber to form an airtightseal therebetween. Lugs 28 project downwardly from the manifold adjacentthe outer surface of the heat chamber and are provided with internallythreaded openings through which to receive the set screws 30 which areadapted to'engage the outer surface of the heat chamber to secure thecap firmly thereto.

As shown in Figures 1 and 2 of the drawing, there is provided in themanifold 16 a multiplicity of circumferentially spaced inlet ports 32which communicate at their inner ends with the annular chamber 18 andterminate at their outer ends adjacent the inner surface of wall 10 ofthe heat chamber. As best shown in Figure 2, these inlet ports aredirected substantially tangential to the inner surface of thecylindrical heat chamber and are also directed slightly downward. Bythis construction, a gas or other fluid ejected from the annular chamber'13 through the ports 32 is projected into the heat chamber adjacent thecylindrical walls thereof with a helical rotation progressing toward thebottom 12 of the heat chamber. The purpose of this rotation is describedin detail hereinafter.

In the embodiment illustrated, heat is produced by the combustion of afuel such as gas. Accordingly, there is provided at the center of thebottom 12 a fuel inlet opening 34 which communicates with a source (notshown) of gas supplied through pipe 36 and regulated by control valve37. Manual or automatic ignition means (not shown) of any conventionaltype may be employed to initiate the combustion of the fuel, whichthereafter is sustained by the oxygen content of the introduced throughthe ports 32.

In the operation of the apparatus illustrated, the gaseous fluid entersthe heat chamber through the fuel inlet opening 34, Where it is ignitedin the usual manner. Airis supplied under pressure to the annularchamber 18 in iighthe'tan'gential ports 32, producing a'rota'tifiglayer'"of"air'adjacent"'the inner 'walls' of the chamber. This rotating layerof air moves downwardly along the wall of the chamber toward the bottomof the latter. the volume of air admitted to the chamber increases, itmoves'in toward the center line of the chamber, as indicated by thearrows 38. The oxygen content of the airmixes with the gaseous fuel,resulting in combustion and the development of a flame 4 6.

When the feed of fuel and'air are in proper adjustment, the flamepattern produced is substantially as illustrated in Figure- 1, whereinthe flame is shown to origin'ate'a spaced'distance above the bottom 12of the chamb'er andto extend'upwardly therefrom toward the exhaust hood14. The flame is generally cylindrical in shape having substantiallyconstant diameter for a major portion of its length, and convergingoutwardly to a pointed tip which terminates adjacent the upper end ofthe chamber. The flame'front is maintained a spaced distancefr'o'inth'e'hinensurface of the wall it to provide'an annular spadefor therotating air layer. The cylindrioal'fla'me envelopes a gas filledcentral core 4 2.

"The rotating layer of air surrounding the flame causes the latter torotate in the same direction. Thus, the products" of'combustion areejected horizontally outward from'the flame front, as indicated by thelight arrows 44, toward the inner front of the rotating air layer. Theseproducts of combustion are substantially hotter than the air front, andhen'ce'the gaseous layer of combustion products'is considerably lessdense than the surrounding layer of air. Moreover, the hot particlespossess substantially greater kinetic energy than the cooler surroundingair particles and therefore possess correspondingly greater straightline velocity. Thus, these high speed heated particles collidetangentially with the slow mov ing particles at the inner front, therebycausing said high speed particles to' be deflected back toward the flamefront. Accordingly, the core layer of hot combustion products and otherhot inert particles, such as the nitrogen content of the air that hasbeen brought into contact with the flame front, is maintainedsubstantially separate from the denser outer layer of cool air whichen-' velopes it. A portion of the surrounding rotating layer of airprogresses inwardly into contact with the flame front and becomes a partof the inner core of hot fluid. This'portion of the air' layer iscontinually replaced by air from the ports 32;. ln 'addition, excess airis introduced into the heat chamber through said ports and, since thisexcess air is prevented from moving into the air. layer surrounding theflame front, it is directed inwardly and upwardly in spiral rotationalong the inner surface of the exhaust hood 14, as indicated by thearrows 38 in Figure 1. This rotating layer of cool air forms anvinsulating envelop for the hot gaseous core entering the, exhaust hoodas it passes from the flame front.

By constricting the discharge opening of the heat chambet, the rotationof the concentric streams of gaseous particles is caused. to increase,in well known manner. This increase in rotational speed functions tomaintain the, gaseous streams. separate for a substantial distance afterleaving the heat chamber, thereby insuring efficient transport of theconcentrated heat layer through delivery pipe 46 to a heat exchanger orother apparatus where the heated layer is converted to useful energy.Since the heated inner core of fluid is maintained separate from thesurrounding insulating envelop the former may be readily separated fromthe latter to provide a concentrated source of heat at the heatexchange.

An illustration of the apparatus and its operation is as follows: A heatchamberwas constructed having a diameter of about five inches and alength of about twelve inches, and a constricted outlet opening of abouttwo inches in diameter. Manufactured gas was supplied-to thechambicii,through the fuel inlet opening at a rate of manifold throughfeed pipe20, and is ejected into the drawn 25 cubic feet per minute.

2,933,296 I H 4 j one cubic foot per minute, and atmospheric air wasinjected into the chamber through the ports ,32 atga pat;

Complete combustion was achieved, as indicated by analysis of theexhaust gases by standard Orsat apparatus. Under these conditions, thetemperature of the outer surface of the heat chamber midway between theends thereof was 76 F. and the temperature of the flame at the samelevel, but 1 inches in from the inner surface of the chamber wall, was1957 F. Temperature readings at the two inch diameter exhaust end of theapparatus indicated the outer surface of thecxhaust outlet to be 97 F.;the temperature of the insulating gas layer one half inch in from theinner surface of the exhaust outlet 'was 124 F.; and the" temperature ofthe inner layer of hot combustion products, three fourths inch in fromthe inner surface of the exhaust outlet, was 2145 F.

In order to determine, the efliciency of transport of the heated gascore enveloped by the insulating gas layer, a Pyrexglasstube, two inchesin diameter and three feet long, was. bent in the shape of a Ujand oneend placed over the exhaust outlet of the "heat chamberl Temperatu remeasurements taken at the opposite end of the glass tube weresubstantially the same as the temperatures.

at the exhaust outlet indicated above.

By standard test procedure, the exhaust from the heat chamber wastransferred to a heat exchanger, and it was determined that 98.3 percentof the total heat value,;of

the fuel was actually transferred as available heat to the x ha eAlthough the means by which heat is developed is illustrated in thedrawing as a system utilizing the combustion of a fuel in the presenceof air, it is to be pointed out here that various other well knownsources of heat may be utilized for the purposes of the presentinvention. For example, the source of heat may be an electricalresistance connected to a suitable source of electric potential. In suchevent, it is preferred that'the resistance element be constructed in theshape of the flame pattern.

other fluid injected into the heat chamber through the.

ports 32. a I I 'To illustrate the operation of apparatus utilizing anelectrical resistance heater, the heat chamber exemplified hereinbeforewas fitted with a 1000 watt resistance element mounted on a basecontoured to the configuration of the flame front illustrated in thedrawing. Air was. admitted through the ports 32 at the rate of volumepreviously exemplified, this amount being substantially more than iscapable of being heated by the resistance element. In'this installationthe temperature of the outer surface of the heat chamber midway betweenthe ends thereof was 72 F., the outer surface of the constricted exhausthood was 83 F., and the gas core enveloped by the insulating gas layerwas 1387 F.

The apparatus of the. present invention may alsoduti lize liquid formsof fuel, such as burner oil, or solid forms of fuel, such as coal. Inthe latter instance, coal is ground to convenient size and fed to theheat chamber a through the opening 34 by. such means as a screw conveyor. The pile of coal deposited upon the central area.

of the bottom 12 of the heat chamber is ignited in the usualmanner toprovide a flame pattern similar to that illustrated in the drawing.

Other sources of heat, e.g-. an atomic pile, may be fluid core and asurrounding insulating layer of air or other fluid, with the temperatureof the heated core being;

at least 20 times the temperature of the insulating layer.

In addition, fluids other than air may be injected through the ports 32to provide the laminar fiow of heated and insulating layers describedhereinbefore. Such fluids capable of use include gases such as nitrogen,carbon dioxide, oxygen, and others; liquids such as water and othernon-combustible liquids; and liquid metals such as mercury and others.

The heat chamber and cap may be constructed of various materials such asmetal, synthetic plastics, glass and others. modated because of the factthat the walls of the heat chamber and exhaust cap are maintained atrelatively low temperatures by virtue of the insulating layersurrounding the heated core.

The heat producing capacity of the apparatus may be varied, as desired,by variations in the dimensions of the apparatus, the quantity of air orother fluid admitted thereto, and/ or the quantity of combustible fueladmitted to the chamber or the heat producing capacity of a resistantelement or atomic pile utilized as a source of heat. In each instancethe characteristic operation of the apparatus is maintained, i.e. thetemperature of the heated core exhaust is at least 20 times thetemperature of the insulating layer surrounding it.

It will be apparent to those skilled in the art that the foregoing andother modifications and changes in structural details may be madewithout departing from the spirit and scope of the present invention.Accordingly, it is to be understood that the foregoing description isprimarily illustrative of the invention, and is not to be considered aslimiting the scope thereof.

Having now described my invention and the manner in which the same maybe used, what I claim as new and desire to secure by Letters Patent is:

Apparatus for producing an insulated directed stream of hot gases,comprising a cylindrical chamber having a closed end, the opposite endof the chamber being tapered Use of synthetic plastic and glass isaccomsmoothly and symmetrically outward to form a constricted centraloutlet, annular air inlet means adjacent the outlet end of the chamberdirecting air toward the closed end along the inner surface of thechamber wall and tangentially thereto, a source of air under pressureconnected to the air inlet means, a central combustible gaseous fuelinlet means in the closed end of the chamber cooperating with the air inthe chamber to provide a flame concentrically within the chamber aspaced distance from the chamber wall and extending toward the outlet, asource of combustible gaseous fuel under pressure connected to thecentral fuel inlet means, means for adjusting the volume and velocity ofcombustible fuel and air to produce at the constricted central outlet acentral rotating core of hot gases separated from the outlet wall by arotating insulating layer of air, and an elongated pipe connected tosaid central outlet to receive said core of hot gases and saidinsulating layer of air and to deliver said core and layer under laminarflow conditions to a point of use.

References Cited in the file of this patent UNITED STATES PATENTS1.452380 1 Hawley Jan. 21, 1920 1,657,698 Schutz Jan. 31, 1928 1,657,725Schutz Jan. 31, 1928 2,047,471 Hepburn et al July 14, 1936 2,582,888Schvenwetter Jan. 15, 1952 2,635,564 Havemanrl Apr. 21, 1953 2,707,444Van Loon May 3, 1955 2,738,776 Burg Mar. 20, 1956 FOREIGN PATENTS843,517 France July 5, 1939 350,051 Great Britain June 11, 1931 704,901Great Britain Mar. 3, 1954 84,740 Norway Dec. 20, 1954

